1. Field of the Invention
The present invention is directed to splittable optical-fiber ribbon products and, more particularly, to optical-fiber ribbon products containing a plurality of sub-unit ribbons that are individually identifiable.
2. Related Art
Optical fiber ribbons consist of a planar array of optical fibers joined together by a resin matrix material or the like. Such ribbons are becoming increasingly popular where optical fibers are used for data transmission and the like. This is due, in part, to the fact that optical fiber ribbons may contain a relatively large number of optical fibers in a package that allows for easy handling and installation. Further, because optical fiber ribbons reduce the need for manipulating individual optical fibers, optical fiber maintenance procedures are simplified. Often, a single cable will include numerous optical fiber ribbons, stacked one on another or otherwise disposed in the cable as sub-units.
It is desirable to be able to easily identify and distinguish optical fiber ribbons one from another and to distinguish constituent elements of a given optical fiber ribbon, both before and after the ribbons are installed in the field for use. Conventionally, ribbon identification has been accomplished by printing characters, such as words, on the ribbon surface or using ink jet printing methods or by applying a bar code to the ribbon, as disclosed in U.S. Pat. No. 5,809,195. Once the identifying characters have been printed on the ribbon (using ink jet methods or the like), the printed characters are susceptible to smearing. Such smearing may render the printed characters illegible. Even when the characters are not smeared, their small size makes it very difficult to read them, particularly in the field where lighting conditions tend to be poor. Also, matching particular printed characters (e.g., particular languages) to particular markets and/or customers can be a difficult and expensive task.
It is an object of the present invention to overcome the drawbacks of the above related art. More particularly, it is an object of the present invention to provide an optical fiber ribbon product which can be easily manufactured and which allows the individual sub-units to be easily identified in the field.
It is a further object of the invention to provide an optical fiber ribbon product in which the individual optical fibers can be accessed easily and quickly. More particularly, it is an object of the present invention to provide an optical fiber ribbon product in which the optical fibers can be accessed by a simple peeling process, thereby reducing the installation time in the field.
The present invention achieves the above and other objects and advantages by providing an optical fiber ribbon product, comprising a first sub-unit including a first plurality of optical fibers arranged substantially in a plane and encapsulated by a first matrix material and a first stripe extending along an outside surface of the first matrix material; and a second sub-unit including a second plurality of optical fibers arranged substantially in a plane and encapsulated in a second matrix material and a second stripe extending along an outside surface of the second matrix material. The first sub-unit and the second sub-unit are disposed adjacent one another and a bonding material at least partially encapsulates the first sub-unit and the second sub-units. The first stripe has a different visual appearance from the second stripe such that the first stripe identifies the first sub-unit and the second stripe identifies the second sub-unit.
According to one aspect of the invention, the bonding material is transparent and fully encapsulates the first stripe and the second stripe. Further, the stripes include either a film strip or a UV curable ink (colored by pigment or dye) applied to the outer surface of the matrix materials. According to a preferred embodiment, the first stripe has a different color from the second stripe.
According to a further aspect of the invention, the stripes are formed by first and second films and the exterior surfaces of the first film and the second film are substantially coplanar with an exterior surface of the bonding material. Further, the first film is bonded to the first matrix material and the second film is bonded to the second matrix material. Therefore, the first matrix material can be stripped by peeling the first film and the second matrix material can be stripped by peeling the second film.
According to a further aspect of the invention, the first film includes a plurality of first individual strips corresponding in number to the first optical fibers and the second film include a second plurality of individual strips corresponding in number to the second optical fibers. The first individual strips are respectively aligned with the first optical fibers and the second individual strips are aligned with the second optical fibers. Therefore, the optical fibers of each of the sub-units can be individually accessed by selectively peeling the film strips.